Congestion control for sidelink transmissions

Abstract

An apparatus for wireless communication based on sidelink accumulates a value, e.g., a token value, based on an accumulation rate of a transmit beam. When the apparatus has a packet for transmission over sidelink, the apparatus determines whether to transmit the packet over the sidelink based on a current accumulation of the value. The accumulation may be based on any of a CBR, a CR, and/or a feedback rate. A base station may measure interference on an access link of the base station and transmit a side link parameter that controls accumulation of a value at a transmitting device for the transmission of sidelink communication based on the measured interference.

What is claimed is: 
     
       1. A method of wireless communication at a wireless device, comprising:
 accumulating a count value over time based on an accumulation rate associated with a transmit beam; 
 identifying a packet for transmission over a sidelink on the transmit beam; 
 determining whether to transmit the packet over the sidelink on the transmit beam based on the count value associated with the transmit beam; and 
 reducing the count value associated with the transmit beam if the wireless device transmits the packet over the sidelink on the transmit beam, a reduction of the count value associated with the transmit beam being based on a priority level associated with the packet. 
 
     
     
       2. The method of  claim 1 , further comprising:
 transmitting the packet over the sidelink on the transmit beam when the count value meets a threshold for the transmit beam; and 
 refraining from transmitting the packet over the sidelink when the count value is less than the threshold for the transmit beam. 
 
     
     
       3. The method of  claim 1 , wherein the count value is accumulated up to a maximum value based at least in part on a channel busy ratio determined by the wireless device. 
     
     
       4. The method of  claim 3 , wherein at least one of the accumulation rate of the transmit beam or the maximum value are based on the channel busy ratio, and wherein the wireless device uses an increased accumulation rate for the transmit beam or an increased maximum value when the channel busy ratio is below a threshold. 
     
     
       5. The method of  claim 1 , wherein the count value is accumulated up to a maximum value based at least in part on a channel occupancy ratio determined by the wireless device. 
     
     
       6. The method of  claim 5 , wherein at least one of the accumulation rate of the transmit beam or the maximum value are based on the channel occupancy ratio, and wherein the wireless device uses an increased accumulation rate for the transmit beam or an increased maximum value when the channel occupancy ratio is below a threshold. 
     
     
       7. The method of  claim 1 , wherein the count value is accumulated up to a maximum value based at least in part on a feedback received by the wireless device. 
     
     
       8. The method of  claim 7 , wherein at least one of the accumulation rate of the transmit beam or the maximum value are based on the feedback received by the wireless device. 
     
     
       9. The method of  claim 8 , wherein the count value is accumulated based at least in part on a positive feedback rate for the wireless device, and the wireless device uses an increased accumulation rate for the transmit beam or an increased maximum value when the positive feedback rate is above a threshold. 
     
     
       10. The method of  claim 8 , wherein the count value is accumulated based at least in part on a negative feedback rate for the wireless device, and the wireless device uses a decreased accumulation rate for the transmit beam or a decreased maximum value when the negative feedback rate is above a threshold. 
     
     
       11. The method of  claim 1 , further comprising:
 receiving information from a base station, wherein at least one of the accumulation rate of the transmit beam or a maximum accumulation value is based on the information received from the base station. 
 
     
     
       12. The method of  claim 1 , wherein the wireless device accumulates a high priority value associated with a first priority level and accumulates a low priority value associated with a second priority level, wherein the first priority level has a higher priority than the second priority level. 
     
     
       13. The method of  claim 12 , further comprising:
 reducing the count value by an amount if the wireless device transmits the packet, wherein the amount is the same for packets of the first priority level and the second priority level. 
 
     
     
       14. The method of  claim 12 , wherein the high priority value is accumulated at a lower accumulation rate than the low priority value. 
     
     
       15. The method of  claim 12 , wherein the high priority value and the low priority value are accumulated up to a maximum value, and wherein a first maximum value associated with the high priority value is lower than a second maximum value associated with the low priority value. 
     
     
       16. The method of  claim 1 , wherein if the wireless device transmits the packet on the transmit beam, the method further comprises:
 reducing the count value by a first amount if the packet corresponds to a first priority level; and 
 reducing the count value by a second amount if the packet corresponds to a second priority level. 
 
     
     
       17. The method of  claim 16 , wherein the count value is accumulated in common for transmissions of the first priority level and transmissions of the second priority level. 
     
     
       18. A method of wireless communication at a base station, comprising:
 measuring interference on a link of the base station; and 
 transmitting, based on the measured interference, a sidelink parameter that controls, in connection with a priority level of a sidelink transmission, accumulation of a count value associated with a transmit beam at a wireless device for transmission of sidelink communication. 
 
     
     
       19. The method of  claim 18 , wherein the interference is based on the sidelink communication. 
     
     
       20. The method of  claim 18 , wherein the sidelink parameter increases at least one of an accumulation rate for the transmit beam or a maximum accumulation value when the interference is below a threshold. 
     
     
       21. The method of  claim 18 , wherein the sidelink parameter decreases at least one of an accumulation rate for the transmit beam or a maximum accumulation value when the interference is above a threshold. 
     
     
       22. An apparatus for wireless communication at a wireless device, comprising:
 a memory; and 
 at least one processor coupled to the memory and configured to:
 accumulate a count value based on an accumulation rate associated with a transmit beam; 
 identify a packet for transmission over a sidelink on the transmit beam; 
 determine whether to transmit the packet over the sidelink on the transmit beam based on the count value associated with the transmit beam; and 
 reduce the count value associated with the transmit beam if the wireless device transmits the packet on the transmit beam, a reduction of the count value associated with the transmit beam being based on a priority level associated with the packet. 
 
 
     
     
       23. The apparatus of  claim 22 , wherein the at least one processor is further configured to:
 transmit the packet over the sidelink on the transmit beam when the count value meets a threshold of the transmit beam; and 
 refrain from transmitting the packet over the sidelink when the count value is less than the threshold of the transmit beam. 
 
     
     
       24. The apparatus of  claim 22 , wherein the count value is accumulated up to a maximum value based at least in part on a channel busy ratio determined by the wireless device, and wherein the wireless device uses an increased accumulation rate for the transmit beam or an increased maximum value when the channel busy ratio is below a threshold. 
     
     
       25. The apparatus of  claim 22 , wherein the count value is accumulated up to a maximum value based at least in part on a channel occupancy ratio determined by the wireless device, wherein the wireless device uses an increased accumulation rate for the transmit beam or an increased maximum value when the channel occupancy ratio is below a threshold. 
     
     
       26. The apparatus of  claim 22 , wherein the count value is accumulated up to a maximum value based at least in part on a feedback received by the wireless device. 
     
     
       27. The apparatus of  claim 22 , wherein the at least one processor is further configured to:
 receive information from a base station, wherein at least one of the accumulation rate of the transmit beam or a maximum accumulation value is based on the information received from the base station. 
 
     
     
       28. The apparatus of  claim 22 , wherein the wireless device accumulates a high priority value associated with a first priority level and accumulates a low priority value associated with a second priority level, wherein the first priority level has a higher priority than the second priority level, wherein the at least one processor is further configured to:
 reduce the count value by an amount if the wireless device transmits the packet, wherein the amount is the same for packets of the first priority level and the second priority level. 
 
     
     
       29. The apparatus of  claim 22 , wherein if the wireless device transmits the packet, the at least one processor is further configured to:
 reduce the count value by a first amount if the packet corresponds to a first priority level; and 
 reduce the count value by a second amount if the packet corresponds to a second priority level. 
 
     
     
       30. An apparatus for wireless communication at a base station, comprising:
 a memory; and 
 at least one processor coupled to the memory and configured to:
 measure interference on a link of the base station; and 
 transmit, based on the measured interference, a sidelink parameter that controls, in connection with a priority level of a sidelink transmission, accumulation of a count value associated with a transmit beam at a wireless device for transmission of sidelink communication.